Part I: Ranking global warming among present-day risks to public health.
Guest essay by Indur M. Goklany
There seems to be no limit to the hyperbole surrounding climate change – and that’s no hyperbole. Numerous politicians have informed us over the years that climate change is one of the most important problems facing mankind. In fact, U.N. Secretary General Ban Ki-moon has called it the defining challenge of our age.”
But is it?
I answer this question in a paper just published in the refereed section of Energy & Environment.
A 2005 review article in Nature on the health impacts of climate change estimated that 166,000 deaths were “attributable” to climate change in 2000. This estimate was derived from a World Health Organization (WHO) sponsored study that even the study’s authors acknowledge may not “accord with the canons of empirical science” (see here). But I will accept this flawed estimate as gospel for the sake of argument.
In the year 2000, however, there were a total of 56 million deaths worldwide. Thus, climate change may be responsible for less than 0.3% of all deaths globally (based on data for the year 2000). This places climate change no higher than 13th among mortality risk factors related to food, nutrition and environment, as shown in the following table.
Specifically, climate change is easily outranked by threats such as hunger, malnutrition and other nutrition-related problems, lack of access to safe water and sanitation, indoor air pollution, malaria, urban air pollution. And had I included other risks to public health beyond environmental, food and nutritional factors (e.g., HIV/AIDS, TB, various cancers, etc.) then climate change would have ranked even lower than 13th.
With respect to biodiversity and ecosystems, today the greatest threat is what it always has been – the conversion of land and water habitat to human uses, i.e., agriculture, forestry, and human habitation and infrastructure. See, e.g., here.
Climate change, contrary to claims, is clearly not the most important environmental, let alone public health, problem facing the world today.
But is it possible that in the foreseeable future, the impact of climate change on public health could outweigh that of other factors?
I will address this question in subsequent blogs.
|Low fruit & vegetables||4||2.7||4.9|
|Unsafe water, poor sanitation||6||1.7||3.1|
|Urban air pollution||9||0.8||1.4|
|Vitamin A deficiency||11||0.8||1.4|
|TOTAL from all causes||55.8||100.0|
Priority ranking of food, nutritional and environmental problems, based on global mortality for 2000. Source: I.M. Goklany, Is Climate Change the “Defining Challenge of Our Age”? Energy & Environment 20(3): 279-302 (2009), based on data from the World Health Organization. Note that malaria isn’t ranked in this table because deaths due to malaria were attributed by WHO to climate change, underweight, and zinc and vitamin A deficiencies.